# A submarine is submerged in the ocean. As the submarine descends deeper into the ocean, the crew must ensure the hull can withstand increasing pressure. Explain why the pressure of the water acting on the hull increases as the submarine descends, and state TWO factors, other than depth, that determine the pressure at any point in a fluid.

> Eduqas GCSE Physics — 3.2 Pressure and pressure differences in fluids · Explain · 4 marks

## Mark scheme (4 marks)

1. As the submarine descends, there is a greater weight / column of water above it
2. This greater weight of water results in a greater force acting on a given area of the hull, so pressure increases
3. One correct factor: the density of the fluid (liquid)
4. Second correct factor: gravitational field strength (g)

## Key terms

- [pressure](https://www.gradenine.co.uk/glossary/pressure)
- [fluid](https://www.gradenine.co.uk/glossary/fluid)
- [depth](https://www.gradenine.co.uk/glossary/depth)

## Related

- [Revision notes for Eduqas GCSE Physics](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

---
Source: [GradeNine](https://www.gradenine.co.uk/q/a-submarine-is-submerged-in-the-22843ab5) · Published by Druglandscape Ltd.